Electronic time delay, lamp control



Nov. 30, 1965 R. M. MURPHY ETAL 3,221,211

ELECTRONIC TIME DELAY, LAMP CONTROL 2 Sheets-Sheet 1 Filed May 20, 1965 FIG. 1

INVENTORS ROBERT M. MURPHY BY JAMES ARTHUR HIRSCH y f A TORNEY Nov. 30, 1965 Filed May 20, 1963 R. M. MURPHY ETAL ELECTRONIC TIME DELAY, LAMP CONTROL 2 Sheets-sheaf. z

LAMP

MOM ENTARY MONOSTABLE POWER ACTUATOR MULTIVIBRATOR AMPLIFIER FIG. 3

FIG-4 INVENTORS ROBERT M. MURPHY JAMES ARTHUR IRSCH TORNE Y United States Patent ()fiice 3,221,211 Patented Nov. 30, 1965 3,221,211 ELECTRONIC TIME DELAY, LAMP CONTROL Robert M. Murphy and James Arthur Hirsch, Indianapolis, Ind., assignors to P. R. Mallory 8: C0., Inc., Indianapolis, Ind., a corporation of Delaware Filed May 20, 1963, Ser. No. 281,630 3 Claims. (Cl. 31584) This invention relates to means and methods for obtaining an electronic time delay and has specific pertinency to an electronic time delay for a lamp control.

In automobiles, when a door is opened by the operator, it is usual for a courtesy lamp to be lighted. However, immediately as the door is closed, the courtesy lamp is extinguished. The present invention affords means whereby even after the door is closed, the courtesy lamp remains lighted for a predetermined time so that the operator has a chance to manipulate the controls under lighted conditions. The lighted condition will exist for a duration depending upon a time delay embodied in this invention.

It is an object of this invention to provide means for creating a delay in the time before a courtesy lamp in a vehicle is extinguished.

Another object of the invention is to provide an electrical time delay utilized with a courtesy lamp of an automobile.

Still another object of the invention is to provide simple means and methods for controlling the time at which a courtesy lamp is extinguished in an automobile.

Yet another object of the invention is a provision of means for extending the time during which illumination may be provided internally of an automobile even after the door is closed.

Other further objects, features and advantages of the invention will be pointed out hereafter and set forth in the appended claims forming a part of the application.

In the accompanying drawing, the figures thereof show a preferred embodiment of the invention and are not to be taken as limiting to the scope thereof.

In the drawing, FIGURE 1 represents an illustrative drawing showing the placement of the electronic time delay lamp control in cooperation with the door of an automobile.

FIGURE 2 is a perspective figure showing the structural aspects of the time delay lamp control utilized in the invention.

FIGURE 3 is a block diagram illustrating a combined assembly of the invention.

FIGURE 4 is an electrical schematic of the circuit used in FIGURE 3 providing the electronic time delay of the invention. 7

Generally speaking, it is the purpose of the invention to provide an extended indication of a momentary occurrence. This is accomplished by introducing a time delay before the indication, in this case a lamp, is turned off.

Referring now to FIGURES 1 and 3. It will be apparent how the device operates. In this case, the opening of the automobile door 10 becomes the momentary actuator 14 of switch 12 which may be closed for no more than a milli-second so as to trigger a mono-stable multivibrator. When this multivibrator 23 is in its unstable state, it supplies an input to a power amplifier 21, which in turn causes current to flow through the output lamp 15 sufficient to light the lamp 15.

FIGURES 2 and 4 illustrate an embodiment of the device. S is the momentary actuator 14, transistor Q is the power amplifier 21, L is the output lamp 15, and B and B are the cells that provide the power to operate the device 12. Reference numeral 23 illustrates the monostable multivibrator which includes capacitors 17 and 19, semiconductors 16, and 18, and diode 20 for establishing its frequency.

With resistor R equal to 10,000 ohms and capacitor C equal to 250 microfarad, timing on the order of 5 to 10 seconds is obtained.

It will be noted that the circuit shown in FIGURE 4 is not necessarily the only circuit that could perform the functions of this device. Among other possible changes are these: the multivibrator 23 might be of different construction, such as 4-layer device construction or bothon or both-off construction or others; the power amplifier 21 might be coupled more conventionally to the multivibrator 23; indeed, the multivibrator 23 may be operated at a sufliciently high power level to operate the lamp 15 directly; the output might be a device other than a lamp 15.

While the invention has been described in detail with respect to certain now preferred examples and embodiments of the invention will it be understood by those skilled in the art after understanding the invention, that various changes and modifications may be made without departing from the spirit and scope of the invention, and it is intended, therefore, to cover all such changes and modifications in the appended claims.

What is claimed is:

1. A time delay circuit for extinguishing an illuminating device after a predetermined time comprising an actuating switch, a monostable multivibrator having a predetermined output frequency and .an illuminating device connected as the load of the multivibrator; the switch and the multivibrator being connected so that operation of the switch will drive the multivibrator to its unstable state and cause current to flow in the illuminating device, the multivibrator operating at a sufficiently high level of 'power to cause substantially full voltage operation of the illuminating device; the multivibrator being means for causing a delay between the time of the operation of the actuating switch and the time of extinguishing of the illuminating device.

2. A time delay circuit for extinguishing an illuminating device after a predetermined time comprising an actuating switch, a monostable multivibrator having a predetermined output frequency, an amplifier connected to the multivibrator, and an illuminating device connected to the output of the amplifier; the switch, the multivibrator, and the amplifier being connected so that operation of the switch will drive the multivibrator to its unstable state and cause the amplifier to become conductive; the multivibrator having means for causing a delay between the time of the operation of the actuating switch and the time of extinguishing of the illuminating device.

3. A time delay circuit for extinguishing an illuminating device after a predetermined time comprising a normally open actuating switch, a monostable multivibra- 4 a tor having a predetermined output frequency, an amplifier References Cited by the Examiner connected to the multivibrator, and an illuminating de- UNITED STATES PATENTS vice connected to the output of the amplifier; the switch, 2 802 142 8/195 Jo o 315 8 the mult' ibrator, and the lifier be'n onne ted so that 1 s n amp 1 gc C 2,837,663 6/1958 Waltz 307 ss.5

closing of the switch Will drive the multivibrator to its un- 5 stable state and cause the amplifier to become conductive;

the multivibrator having means for causing a delay be- JOHN HUCKERT Pnmary Exammer' tween the time of the closing of the actuating switch DAVID J. GALVIN, D. E. PITCHENIK,

and the time of extinguishing of the illuminating device. Assistant Examiners. 

1. A TIME DELAY CIRCUIT FOR EXTINGUISHING AN ILLUMINATING DEVICE AFTER A PREDETERMINED TIME COMPRISING AN ACTUATING SWITCH, A MONOSTABLE MULTIVIBRATOR HAVING A PREDETERMINED OUTPUT FREQUENCY AND AN ILLUMINATING DEVICE CONNECTED AS THE LOAD OF THE MULTIVIBRATOR; THE SWITCH AND THE MULTIVIBRATOR BEING CONNECTED SO THAT OPERATION OF THE SWITCH WILL DRIVE THE MULTIVIBRATOR TO ITS UNSTABLE STATE AND CAUSE CURRENT TO FLOW IN THE ILLMUNIATING DEVICE, THE MULTIVIBRATOR OPERATING AT A SUFFICIENTLY HIGH LEVEL OF POWER TO CAUSE SUBSTANTIALLY FULL VOLTAGE OPERATION OF THE ILLUMINATING DEVICE; THE MULTIVIBRATOR BEING MEANS FOR CAUSING A DELAY BETWEEN THE TIME OF THE OPERATION OF THE ACTUATING SWITCH AND THE TIME OF EXTINGUISHING OF THE ILLUMINATING DEVICE. 